CMP0022: Plain target_link_libraries must populate link interface

The CMP0022 NEW behavior is that the INTERFACE_LINK_LIBRARIES property
exactly defines the link interface.  The plain target_link_libraries
signature says linking is transitive by default, so it should populate
the property.

Teach the target_link_libraries plain signature to populate the
INTERFACE_LINK_LIBRARIES regardless of the CMP0022 setting.  Refactor
the cmTarget::ComputeLinkInterface checks that warn when the policy is
not set to compare the new property to either the explicitly set old
link interface properties or the link implementation fallback for all
linkable target types, not just static libraries.

This fixes a regression in 2.8.12.0 that caused target_link_libraries to
not implement transitive linking in the plain signature once the policy
CMP0022 is set to NEW.

7 files changed, 23 insertions, 11 deletions

diff --git a/Tests/RunCMake/CMP0022/CMP0022-NOWARN-shared-stderr.txt b/Tests/RunCMake/CMP0022/CMP0022-NOWARN-shared-stderr.txt
new file mode 100644
index 0000000..10f3293
--- /dev/null
+++ b/Tests/RunCMake/CMP0022/CMP0022-NOWARN-shared-stderr.txt
@@ -0,0 +1 @@
+^$
diff --git a/Tests/RunCMake/CMP0022/CMP0022-NOWARN-shared.cmake b/Tests/RunCMake/CMP0022/CMP0022-NOWARN-shared.cmake
new file mode 100644
index 0000000..57c3ed0
--- /dev/null
+++ b/Tests/RunCMake/CMP0022/CMP0022-NOWARN-shared.cmake
@@ -0,0 +1,8 @@
+enable_language(CXX)
+
+add_library(foo SHARED empty_vs6_1.cpp)
+add_library(bar SHARED empty_vs6_2.cpp)
+target_link_libraries(bar foo)
+
+add_executable(zot empty.cpp)
+target_link_libraries(zot bar)
diff --git a/Tests/RunCMake/CMP0022/CMP0022-WARN-empty-old-stderr.txt b/Tests/RunCMake/CMP0022/CMP0022-WARN-empty-old-stderr.txt
index 6d519f0..6a6a0c7 100644
--- a/Tests/RunCMake/CMP0022/CMP0022-WARN-empty-old-stderr.txt
+++ b/Tests/RunCMake/CMP0022/CMP0022-WARN-empty-old-stderr.txt
@@ -3,14 +3,16 @@ CMake Warning \(dev\) in CMakeLists.txt:
   interface.  Run "cmake --help-policy CMP0022" for policy details.  Use the
   cmake_policy command to set the policy and suppress this warning.
 
-  Target "bar" has a INTERFACE_LINK_LIBRARIES property which differs from its
-  LINK_INTERFACE_LIBRARIES properties.
+  Target "bar" has an INTERFACE_LINK_LIBRARIES property.  This should be
+  preferred as the source of the link interface for this library but because
+  CMP0022 is not set CMake is ignoring the property and using the link
+  implementation as the link interface instead.
 
   INTERFACE_LINK_LIBRARIES:
 
     foo
 
-  LINK_INTERFACE_LIBRARIES:
+  Link implementation:
 
     \(empty\)
 
diff --git a/Tests/RunCMake/CMP0022/CMP0022-WARN-static-stderr.txt b/Tests/RunCMake/CMP0022/CMP0022-WARN-static-stderr.txt
index e41133a..1370c5e 100644
--- a/Tests/RunCMake/CMP0022/CMP0022-WARN-static-stderr.txt
+++ b/Tests/RunCMake/CMP0022/CMP0022-WARN-static-stderr.txt
@@ -3,10 +3,10 @@ CMake Warning \(dev\) in CMakeLists.txt:
   interface.  Run "cmake --help-policy CMP0022" for policy details.  Use the
   cmake_policy command to set the policy and suppress this warning.
 
-  Static library target "bar" has a INTERFACE_LINK_LIBRARIES property.  This
-  should be preferred as the source of the link interface for this library.
-  Ignoring the property and using the link implementation as the link
-  interface instead.
+  Target "bar" has an INTERFACE_LINK_LIBRARIES property.  This should be
+  preferred as the source of the link interface for this library but because
+  CMP0022 is not set CMake is ignoring the property and using the link
+  implementation as the link interface instead.
 
   INTERFACE_LINK_LIBRARIES:
 
diff --git a/Tests/RunCMake/CMP0022/CMP0022-WARN-stderr.txt b/Tests/RunCMake/CMP0022/CMP0022-WARN-stderr.txt
index 93c0ab3..f849be2 100644
--- a/Tests/RunCMake/CMP0022/CMP0022-WARN-stderr.txt
+++ b/Tests/RunCMake/CMP0022/CMP0022-WARN-stderr.txt
@@ -3,8 +3,8 @@ CMake Warning \(dev\) in CMakeLists.txt:
   interface.  Run "cmake --help-policy CMP0022" for policy details.  Use the
   cmake_policy command to set the policy and suppress this warning.
 
-  Target "bar" has a INTERFACE_LINK_LIBRARIES property which differs from its
-  LINK_INTERFACE_LIBRARIES properties.
+  Target "bar" has an INTERFACE_LINK_LIBRARIES property which differs from
+  its LINK_INTERFACE_LIBRARIES properties.
 
   INTERFACE_LINK_LIBRARIES:
 
diff --git a/Tests/RunCMake/CMP0022/CMP0022-WARN-tll-stderr.txt b/Tests/RunCMake/CMP0022/CMP0022-WARN-tll-stderr.txt
index 6370b24..f672285 100644
--- a/Tests/RunCMake/CMP0022/CMP0022-WARN-tll-stderr.txt
+++ b/Tests/RunCMake/CMP0022/CMP0022-WARN-tll-stderr.txt
@@ -3,8 +3,8 @@ CMake Warning \(dev\) in CMakeLists.txt:
   interface.  Run "cmake --help-policy CMP0022" for policy details.  Use the
   cmake_policy command to set the policy and suppress this warning.
 
-  Target "bar" has a INTERFACE_LINK_LIBRARIES property which differs from its
-  LINK_INTERFACE_LIBRARIES properties.
+  Target "bar" has an INTERFACE_LINK_LIBRARIES property which differs from
+  its LINK_INTERFACE_LIBRARIES properties.
 
   INTERFACE_LINK_LIBRARIES:
 
diff --git a/Tests/RunCMake/CMP0022/RunCMakeTest.cmake b/Tests/RunCMake/CMP0022/RunCMakeTest.cmake
index 8e5824a..9123f6d 100644
--- a/Tests/RunCMake/CMP0022/RunCMakeTest.cmake
+++ b/Tests/RunCMake/CMP0022/RunCMakeTest.cmake
@@ -4,6 +4,7 @@ run_cmake(CMP0022-WARN)
 run_cmake(CMP0022-WARN-tll)
 run_cmake(CMP0022-WARN-static)
 run_cmake(CMP0022-WARN-empty-old)
+run_cmake(CMP0022-NOWARN-shared)
 run_cmake(CMP0022-NOWARN-static)
 run_cmake(CMP0022-NOWARN-static-link_libraries)
 run_cmake(CMP0022-export)